But it's still not fully secure with some assets not in secure mode. I used Httpfox to check all the HTTP requests and all HTTP requests are correctly redirected to HTTPS. Now I don't know why it's still not fully secure. I thought redirecting all HTTP assets to HTTPS would be the deal in this case? Is it?

If not, it seems the only option left for me is to manually change all HTTP assets (href, src, etc.) to HTTPS across all the content. Is there any easy way to achieve this for the entire WP blog? A plugin? This doesn't seem right to me as I'm afraid it would neglect one asset or two on some of the posts or pages.